1. Field of Invention
This invention relates to controlling sheet placement in finishing devices.
2. Description of Related Art
Devices that process sheets of paper, such as high-speed printers, digital copiers and photocopiers, often require finishing operations to be performed. Such a finishing device causes the paper sheets to be deposited in manner either selected by the user or in a default fashion.
Many finishing devices and sheet stacking devices are known in the sheet handling equipment industry, and involve collating or stacking sheets into sets of sheets and finishing each set of sheets by stapling or binding prior to depositing the finished sets of sheets onto a collection tray. Commercially-available designs for finishing devices are currently either too slow for efficient use in high-speed photocopiers, or present an excessive footprint and thereby consume greater volume and surface area in an office space than is desirable.
Conventional finishing devices convey paper sheets horizontally to control their travel for processing. Such configurations require considerable volume for the mechanisms to controllably move the paper sheets. Finishing devices having vertical configurations present either uneven stacking from flutter as the sheets drop or require volume-intensive mechanisms to control the descent of the sheets.
A high-speed finishing device confined to a small footprint requires that the aerodynamic flutter of the incoming sheets be controlled. A sheet passes through one of a series of diverter gates, depending on the size of the sheet. As the sheet is ejected through a diverter gate, the sheet drops onto a retracting temporary compiler structure.
This invention provides devices and methods for controllably dropping a sheet in a finishing device, such as from an image-forming device.
This invention separately provides devices and methods for reducing flutter in dropped sheets.
This invention separately provides devices and methods for reducing drop time in dropped sheets.
This invention separately provides devices and methods for suppressing forward and rearward motion of dropped sheets.
In various exemplary embodiments, the sheet passes through a retracting temporary compiler structure and continues its descent. At the same time, rear paper suppressor structures provided on a diverter assembly swing down and forward to push the trailing edge of the sheet forward, preventing rearward motion of the sheet. Front paper suppressor slats or baffles provided on a front dampener swing down and backwards to intercept the leading edge of the sheet. These baffles operate to prevent the sheet from moving past the front register gate and to pitch the leading edge of the sheet downward. This enables the sheet to stack evenly on the collection tray after passing under the retracting temporary compiler.
In various exemplary embodiments, the diverter assembly for the rear paper edge suppressor slats can be positioned by a diverter gate positioning motor through a gate belt suspended between two pulleys. In various exemplary embodiments, the rear paper edge suppressor slats are swung by a trail edge suppression drive motor through a positioning system driven by a drive motor through a clutch.
These and other features and advantages of this invention are described in, or are apparent from, the following detailed description of various exemplary embodiments of the systems and methods according to this invention.